This 8-piece colored pen set features a range of ink colors. These pens offer the same quality Pigma Ink performance as the regular Pigma Micron Pens with a plastic nib suitable for everyday, multi-purpose writing. The durable plastic nib provides skip-free writing and a fine or medium line width (.4mm to .5mm) can be achieved based on writing pressure. The polyacetal nib structure allows for smooth ink-flow whether writing fast or slow, for right or left handed users writing at an angle. Ideal for use on paper. Pigma archival quality ink is waterproof, chemical and fade resistant, bleed free, quick drying and pH neutral.